This disclosure relates to self-repairing metal alloy matrix composites, methods of manufacture and use thereof and articles comprising the same.
Metal materials, such as aluminum alloys, have been investigated for use in aerospace equipment. Although properties of aluminum such as cost and weight are desirable for aerospace and other lightweight material applications, during operation such materials can be subjected to physical stresses due to cyclic loading, resulting in the formation of fatigue cracks, and subsequently, may lead to fatigue failure.
To repair fatigue cracks, additional materials, skilled application of a repair technique and/or direct access are generally utilized. For example, repair methods may include drilling the crack tip to blunt the crack in order to prevent further crack propagation, grinding out the crack and using weld overlays to obtain the desired part thickness, using a doubler to reinforce the material surrounding the crack, applying selective plating over the crack, applying polymeric fillers to fill the crack, or applying thermal sprays over the crack. However, since these repair techniques involve additional materials, skilled external application and/or direct access, these techniques may not be desirable in aerospace applications, such as those in space flight. Further, repair techniques involving doublers pose challenges with regard to bonding and surface preparation in aerospace application. In addition, weld overlays, while suitable for some metal alloys such as steel-based alloys, pose challenges in terms of reduced strength when applied to aluminum-based structural materials.
It is therefore desirable to develop metal alloy matrix composites and methods of making thereof which have self-repairing capabilities to facilitate the closure and/or repair of fatigue cracks and/or to avoid one or more of the challenges described above.